Recently, cases of organ transplantation have increased according to the development of surgical operation technique and medicines such as immunosuppressant. A number of patients are in need of transplants but many organs are not kept in a proper condition for use and thus discarded. Thus, it has been reported that there are still many patients awaiting transplant surgeries. It is most preferable that an organ is transplanted to a recipient as soon as it is removed from a donor. However, many transplant surgeries are not done immediately as such. Therefore, the extended time of storage and improved quality of organs to be transplanted by improving storage method remain as urgent technical problems.
In these days, low temperature storage (below 20° C., typically below 4° C.) is utilized to preserve organs, which inhibits metabolism rather than provides appropriate physiological conditions in vivo. A various kind of preserving solutions for such method have been developed and used clinically.
At an early stage, Euro-Collin's solution was used. Recently, UW solution (University of Wisconsin, Wahlberg, J. A., et al., Transplantation, 43, pp. 5-8, 1987) has been developed, which is useful as a preserving solution for liver, intestine and kidney as well as pancreas and capable of preserving liver up to 24 hours experimentally. However, in clinical tests, it is used for a shorter period to protect the patients. Thus, preserving solutions or additional agents capable of maintaining viability of organs for more extended time and providing effective storage of organs are strongly required to be developed.
Indole and indazole compounds according to the present invention have a very suitable structure to medical purpose, and a number of researches on compounds having an indole core structure have been published. For example, their activities to glucokinase (WO2006/112549), usefulness as anti-cancer drug and cardiovascular angiogenesis inhibitor (WO95/07276) and as antibiotics (WO2004/018428) are representatively known.